1. Field of the Invention
The present invention relates to, for example, a sheet processing system that packs a bunch of sheets such as securities.
2. Description of the Related Art
A sheet processing system processing sheets such as securities is composed of a sheet processor that processes the sheets, a conveyor that conveys a bundle discharged by the sheet processor, and a packing device that packs a predetermined number of bundles conveyed by the conveyor.
The sheet processor takes out and conveys collectively supplied sheets one by one. A determination section determines whether each of the sheets is true or false and whether the sheet is normal or damaged. On the basis of the determinations, the sheet processor sorts and collects the sheets. When the number of the collected sheets reaches, for example, 100, the sheets are passed to a bundling section, which then bundles the sheets using a small band to form a bundle. The bundle thus formed is discharged by the sheet processor and fed to the conveyor, on which the bundle is conveyed. Ten bundles are further collectively bundled together using a large band to form a bunch (see, for example, Jpn. Pat. Appln. KOKAI Publication No. 10-143710).
The bundle formed using the small band is slightly wider at the opposite ends. Since the position of the small band is normally away from a longitudinally central part of the sheets, the width of the bundle at one end is different from the width of the bundle at the other end.
However, in packing a predetermined number of bundles together, the sheet processor described in Jpn. Pat. Appln. KOKAI Publication No. 10-143710 bundles every 10 bundles with all the small bands around the bundles aligned with one another in the same direction. This may disadvantageously result in a nonuniform thickness and thus prevent the bundles from being packed so as to have an appropriate shape.